Most of the picturesque old sugar mills dotting the island's landscape were built early in the period of 1750 to 1800. A few estates had two windmills, and in addition, many had auxiliary ox or mule mills, for when the cane was ready, it must be cut, and when it was cut it must be ground quickly to avoid fermentation. During "crop" speed was essential; the mills ground incessantly, day arid night, with the men working in shifts.
THE ANIMAL MILL
This consisted of the central grinding machinery under a shed surrounded by an earthenwork or stonework elevated rim, with the appearance of a circular crater. Along the top of the rim the oxen, mules or horses walked on a path. A long pole ran from the animals' harness to the center shaft of the machinery, thus turning it and providing the power for the grinding.
The earliest animal mills did well if they ground enough canes in one hour to yield from 300 to 350 gallons of juice. Later models, using up to ten mules, produced some 500 gallons an hour. Allowing four hours out of the twenty-four for loss of time, the return per day could be 10,000 gallons of juice, being equal to 36 hogsheads of sugar at 16-cwt. for every week during the crop season.
A windmill is essentially a simple contrivance, yet great force is required to run it to overcome the resistance of the cane being ground. In the early days in St. Croix, the machinery inside the mill consisted principally of three upright iron-plated rollers cylinders. The middle one, to which moving-power was attached from above turned the other two by means of cogs.
Between these rollers the canes were compressed. They passed through the first and second rollers; were turned around the center one by a circular framework or screen sometimes called the "dumb returner," and were forced back through the second and third rollers.
This operation squeezed the cane nearly dry. The juice ran downhill in a leaded trough to the factory below. The leftover fibre refuse, called bagasse was later used as fuel under the coppers in which the juice was boiled.
The St. Croix mills were a Dutch type, in which only the dome was turned, carrying the axle and sails with it into the required position. The masonry top of the mill had a wooden (later cast iron) rim on which ran small rollers on which the dome rested. The turning of the dome, so that the four canvas sails on their wooden arms would face directly into the wind, was accomplished by means of a long pole at an angle running down nearly to the ground from the dome. A whole crew of men sometimes had to rush to shift the pole when the wind blew stronger or changed direction.
The problems of controlling the sails to give an even grinding operation were not easily solved. There was at first no means of reefing, and sometimes a gusty wind revolved it all so fast that the sails were tom off. Later, a way was devised for men to climb up to reef the sails individually.
The first successful automatic reefing apparatus was invented in 1780, giving controlled motion to the grinding for the first time. In 1807, a further improved method of reefing the big sails was introduced. This was a simple arrangement of movable wooden shutters or louvers in part of the sails instead of canvas.
Today on St. Croix these stone windmills are highly prized for their haunting quality of beauty and as reminders of the special historic heritage of the island. Much of the old machinery was sold for scrap or lies rusting in the underbrush. The mill at Whim Greathouse has been restored to working order by the Landmarks Society so that visitors and islanders can visualize its use.
THE STEAM MILLS
The first steam mill for grinding cane was put into use at Estate Hogansborg for the crop of 1816, but it was so balky and broke down so often that other plantation owners remained unconvinced that steam was worth the expense. It was not until the 1830's that other steam mills made their appearance at Whim and another estate. Wind power and slaves were still cheaper than steam.
However, just four years after the slaves were freed in 1848, there were some fifty steam engines here.
In the yard of La Grange stands a piece of narrow-gauge railway track with a small type of flatcar on it. This is one of the last remnants of a little rail line which once ran along the northwest shore carrying cane to La Grange factory. Another, south shore, railway led to the factory at Bethlehem which served the estates in the center of the island. Reportedly, the entire track, tiny steam engine and strings of flatcars were sold years ago to Mexico.
In 1876, the Danish government underwrote the building of five large cane crushing stations at Estates Fair Plain, Glynn, Barren Spot, La Grande Princess and at Peter's Rest, which was the largest station. From these estates, cane juice was pumped through miles of pipe lines to huge tanks at Orange Grove where Cruzana now is, and on down to a Central Factory on the shore near Christiansted.
Today the grinding of cane commercially on the island has come to a final stop after over three hundred years.